Obstetrics and Gynecology, MedStar Washington Hospital Center, Washington, DC.
Georgetown University School of Medicine, Washington, DC.
Am J Obstet Gynecol MFM. 2020 Aug;2(3):100103. doi: 10.1016/j.ajogmf.2020.100103. Epub 2020 Mar 21.
It is hypothesized that pregnancy causes time-limited physiologic adaptations of the reproductive system, such as increased blood flow to the uterus. With long interpregnancy intervals, those adaptations may regress, and maternal physiologic characteristics may revert to those of primigravid women. Therefore, it is plausible that long interpregnancy interval is associated with cesarean delivery, especially due to arrest disorders (failed induction of labor, arrest of dilation, or arrest of descent).
To examine the association between interpregnancy interval and cesarean delivery due to arrest disorders in multiparous women without a history of cesarean delivery.
This was a retrospective cohort study of all women who had more than 1 singleton pregnancy at 23 weeks' gestation or greater at MedStar Washington Hospital Center from January 2009 to June 2018. We defined the interpregnancy interval as the duration from the birth of the preceding offspring to the date of conception of the index offspring. We a priori decided to categorize women based on the interpregnancy interval (less than 18 months, 18-59 months, and 60 months or greater). Our primary outcome was cesarean delivery due to arrest disorders. We also examined overall cesarean delivery and cesarean delivery due to nonreassuring fetal heart tracing. Multivariable logistic regression was performed to calculate adjusted odds ratios and 95% confidence intervals, controlling for predefined covariates.
Of 2741 women, 1143 (41.7%), 1369 (49.9%), and 229 (8.4%) had an interpregnancy interval of less than 18 months, 18-59 months, and 60 months or more, respectively. After adjusting for confounders, an interpregnancy interval of 60 months or more compared to an interpregnancy interval of 18-59 months was associated with increased odds of cesarean delivery due to arrest disorders (4.8% vs 1.3%; adjusted odds ratio, 3.06; 95% confidence interval, 1.34-6.97) and cesarean delivery due to arrest of dilation (3.1% vs 0.7%; adjusted odds ratio, 3.24; 95% confidence interval, 1.10-9.59). An interpregnancy interval of less than 18 months compared to an interpregnancy interval of 18-59 months was associated with decreased odds of cesarean delivery due to nonreassuring fetal heart tracing (2.4% vs 4.1%; adjusted odds ratio, 0.55; 95% confidence interval, 0.32-0.92).
An interpregnancy interval of 60 months or greater compared to an interpregnancy interval of 18-59 months was associated with increased odds of cesarean delivery due to arrest disorders. Beneficial effects on postpartum adaptations in the reproductive system may regress as interpregnancy interval increases.
据推测，妊娠会导致生殖系统的生理性适应具有时间限制，例如增加流向子宫的血流量。如果两次妊娠之间的间隔时间较长，这些适应可能会退化，并且产妇的生理特征可能会恢复到初产妇的水平。因此，较长的两次妊娠之间的间隔时间与剖宫产分娩有关，特别是由于阻滞性疾病（引产失败、扩张阻滞或下降阻滞）。
检查在没有剖宫产史的多产妇中，两次妊娠之间的间隔时间与阻滞性疾病导致的剖宫产之间的关系。
这是一项回顾性队列研究，纳入了 2009 年 1 月至 2018 年 6 月在 MedStar Washington 医院中心妊娠 23 周或以上的所有单胎妊娠多于 1 次的女性。我们将两次妊娠之间的间隔时间定义为上次分娩后到本次妊娠受孕日期的持续时间。我们根据两次妊娠之间的间隔时间（<18 个月、18-59 个月和≥60 个月）预先决定对女性进行分类。我们的主要结局是阻滞性疾病导致的剖宫产。我们还检查了总体剖宫产和非可靠胎儿心图导致的剖宫产。采用多变量逻辑回归计算调整后的优势比和 95%置信区间，控制了预先定义的协变量。
在 2741 名女性中，分别有 1143（41.7%）、1369（49.9%）和 229（8.4%）的两次妊娠间隔时间<18 个月、18-59 个月和≥60 个月。调整混杂因素后，与 18-59 个月的两次妊娠间隔时间相比，间隔时间≥60 个月与阻滞性疾病导致的剖宫产（4.8% vs 1.3%；调整后的优势比，3.06；95%置信区间，1.34-6.97）和扩张阻滞导致的剖宫产（3.1% vs 0.7%；调整后的优势比，3.24；95%置信区间，1.10-9.59）的几率增加有关。与 18-59 个月的两次妊娠间隔时间相比，<18 个月的两次妊娠间隔时间与非可靠胎儿心图导致的剖宫产（2.4% vs 4.1%；调整后的优势比，0.55；95%置信区间，0.32-0.92）的几率降低有关。
与 18-59 个月的两次妊娠间隔时间相比，间隔时间≥60 个月与阻滞性疾病导致的剖宫产几率增加有关。随着两次妊娠之间的间隔时间增加，生殖系统产后适应性的有益影响可能会退化。
